Automatic gripping chuck



Feb. 1, 1966 E. F. OBEAR 3,232,629

AUTOMATIC GRIPPING CHUCK Filed July 1, 1960 3 Sheets-Sheet 1 Is 68 F162 [7 6916 INVENTOR.

EDWARD- F. OBEAR ATTORNEY Feb. 1, 1966 AUTOMATIC GRIPPING CHUCK Filed July 1, 1960 3 Sheets-Sheet 2 FIG.5

INVENTOR. EDWARD F. QBEAR BZJWTW ATTORNEY E. F. OBEAR 3,232,629

Feb. 1, 1966 E. F. OBEAR 3,232,629

AUTOMATIC GRIPPING CHUCK Filed July 1. 1960 5 Sheets-Sheet 5 INVENTOR. EDWARD F. OBEAR ATTORNEY United States Patent 3,232,629 AUTQMATIC GRIPPENG CHUCK Edward F. Obear, Los Angeles, Calif. (94% W. Florence Ave., Inglewood 1, Calif.) Filed July 1, 1960, Ser. No. 40,274 7 (Ziaims. (Cl. 2791i)6) This application is a continuation-in-part application of my copending application for a Pipe-Working Machine, Serial No. 760,323, filed September 11, 1958, now abancloned.

This invention relates to a pipe working machine and more particularly to a machine for per-forming various operations on workpieces, such as rods, or the like including thread cutting, cut-off and reaming operations.

An object of this invention is to provide a machine which automatically grips a workpiece when a drive means thereof is actuated in one direction, whereby the workpiece is securely gripped and subsequently rotated for the performance of the various operations referred to above.

Another object of this invention is to provide new and improved gripping means for positively and securely gripping the workpiece, which is automatically operated by actuation of a drive means in one direction to grip the workpiece, whereby continued rotation is transmitted through the gripping means to rotate the workpiece, and whereby rotation of the drive means, in a reverse direction, causes the gripping means to automatically ungrip the workpiece.

A further object of this invention is to provide new and improved gripping means of the character described, which are axially spaced along the axis of the pipe to provide a more stable support for the workpiece and which automatically centers the workpiece within the ma chine for centerless support and rotation thereof.

Yet a further object of this invention is to provide new and improved gripping means of the character described which are independently operable at spaced positions along the workpiece to accurately and securely grip the workpiece at corresponding spaced intervals.

Another object of this invention is to provide a new and improved gripping means of the character described which automatically securely grips the workpiece at the spaced intervals regardless of variations of the diameter of the workpiece at the spaced intervals.

It is a general object of this invention to provide a new and improved workpiece working machine which overcomes disadvantages of prior methods and machines heretofore intended to accomplish generally the same purpose.

These and other objects will be more apparent from the following detailed description, drawings and appended claims.

In the drawings:

FIGURE 1 is a plan view, in elevation, of a workpiece working machine designed and constructed in accordance with this invention, with parts broken away for greater clarity;

FIGURE 2 is a vertical cross-sectional view as seen substantially along a line 22 of FIGURE 1 with parts shown in elevation;

FIGURE 3 is an enlarged fragmentary vertical cross sectional view as taken on a line 3-3 of FIGURE 2;

FIGURE 4 is an enlarged vertical cross-sectional view as taken on a line 4-4 of FIGURE 2;

FIGURE 5 is a fragmentary view, similar to FIGURE 4, showing the gripping means thereof in a changed position;

FIGURE 6 is an enlarged vertical cross-sectional view as taken along a line 6-6 of FIGURE 4, omitting the housing and cover thereof for greater clarity.

Referring more particularly to FIGURES 1-6, inclusive, of the drawings, there is shown, by way of illustration, but not of limitation, an embodiment of a workpiece working machine, generally designated by the numeral 15 for supporting, in gripping relationship, and rotating a workpiece 16, which may be in the form of a tubular pipe, solid rod, or the like, for cutting helical threads 17 at one end of the workpiece by means of thread-cutting means generally referred to by the numeral 18, reaming the internal diameter of the workpiece by means of reaming means 19 and subsequently cutting off the pipe at a desired length by cut-off means 21, thereby forming a complete machine capable of performing all of these operations.

The machine 15 comprises support means 22, in the form of a substantially hollow housing 23 having opposing side walls 24 and 26, an end wall 27 spanning the side walls at one end, an integral oil or lubricant storage pan 28, and a pair of transverse webs or walls 29 and 31 spanning the side walls adjacent another end.- The support means 22, by means of its transverse walls 29 and 31, serves to rotatably support a hollow shaft 32.

It has been observed, in practice, that standard workpieces, such as pipes or rods, or the like, often vary in their diametrical outer surfaces, along the length of the workpiece, due to commercial tolerances, whereby the outer surface of the workpiece subjected to one set of gripping members may vary considerably from the outer diamctrical surface subjected to the other set of gripping members spaced therefrom. In such event, the set of gripping members grippingly engaging a larger diameter on the workpiece might result in failure of the other set of gripping means to firmly grip the area of pipe adjacent thereto, thereby causing rotation of the workpiece by one set of gripping members while the other set of gripping members are not fully engaged with the workpiece area adjacent thereto. Such a condition usually results in an untrue centerless support of the workpiece, a vibration in the workpiece due to a singular support at one area thereof and a loose support at another area thereof which can produce an excessive wobbling of the workpiece and precludes accurate threading there of by the thread-cutting means described.

To obviate this the hollow shaft 32 is formed in two parts consisting of a pair of aligned hollow shafts 33 and 34 which serve as chuck members. They are rotatably supported as on the transverse walls 29 and 31, respectively, of the support 22. They are in end-to-end coaxial relationship for receiving a workpiece 16 through the axial passageway formed by the aligned hollow shafts.

The walls 29 and 31 are provided with aligned bores 38 in which are mounted annular ballbearings 39 to provide low friction support of the two shaft parts 33 and 34.

The hollow shaft 33 is provided with an outwardly extending annular flange 41 at the outer end thereof and the shaft 34 has a corresponding flange 42 opposite the flange 41. The outer faces 43 of the flanges 41 and 42 are substantialy fiat and perpendicular to the axis of the shaft 32. They have outwardly extending arcuate extensions 44 for rotatably supporting an annular ring gear 45 on the outer surface 43 of the flange 41 and a ring gear 46 on the outer surface 43 of flange 42.

The extensions 44, as best seen in FIGURE 4, have outer arcuate surfaces 47, each surface 47 having a common radial distance from the axis 48 of the hollow shaft 32, thereby forming arcs of a common circle, and having a bearing fit with an internal surface of internal gear teeth 49 of the ring gears 45, 46. The gears 45, 46 are thereby adapted to be supported by the extensions 44 of each flange 41, 42 and rotate freely thereon. The ring gears further include external gear teeth 51 on the outer periphery thereof, each ring gear 45, 46 being in engagement with one of adjacent gears 52 and 53, respectively, mounted on the ends of a double ended shaft 54 of a motor 55, whereby driving of the gears 52, 53 by means of the motor 55 rotates the ring gears 45 and 46, respectively. The motor 55 is preferably of a reversible type for purpose which will be hereinafter described.

Each flange 41 42, is further provided with outwardly extending stub shafts 56 (see FIGS. 4, Sand 6) upon which are rotatably supported a plurality of gripping members 57. As best seen in FIGURES 4 and 5, each gripping member 57 is provided with segmental gear teeth 58, complementary to the gear teeth 49 of the ring gears 45 and46, on an arcuate outer surface, The armate outer surface is substantially coaxial with the axis of its corresponding stub shaft 56. The inner end of each gripping member is provided with a segmental, arcuate, serrated edge 59 to form a gripping surface adapted to selectively engage the workpiece 16 extending through the hollow shaft 32.

As will now be more clearly understood from the foregoing description, when the motor 55 is actuated to rotate in one direction, the gears 52 and 53 are rotated, as an example, in a counterclockwise direction, to drive the ring-gears 45 and 46 in a counterclockwise direction as viewed in FIGURE 4, whereby each gripping member 57 is rotated by the teeth 49-58, with the stub shafts 56 as a pivot, to bring the serrated edge 59 thereof towards the axis 48 of the hollow shaft 32 and thereby grip the workpiece 16 in spaced relationship around its outer eripheral surface.

It will be noted that the hollow shafts 33 and 34 are independently rotatable by a drive means 55. They thus independently actuate the gripping means or members 57 rotatably disposed on the pivot points or stub shafts 56 extending outwardly from the flanges or chuck plates 41 and 42.

Theadjacent ends of the hollow shafts 33 and 34, respectively, are telescopingly received, one within the other, for centralsupport of the shaft 32, so that one of the hollow shafts is rotatable relative to the other and is supported thereby. In practice a sleeve 35 is secured as by welding or the like over and around the end of the shaft 34. It extends beyond the end of the shaft 34 and slidably receives therewithin the adjacent end of the shaft 33. Thus the shafts 33 and 34 are rotatable relative to each other, but at the same time serve to provide support for each other at their adjacent facing ends.

For frictionless rotation of the end of the shaft 33 within the sleeve 35, lubricant passages are preferably provided, such as a pair of annular passages 36 having a transverse(longitudinal relative to the sleeve) passage 37 communicating with a lubricant fitting 40 through which lubricant may be injected into the passages 36 and 37. It is to be understood that an oilless bushing may be provided within the open end of the sleeve 35 if desired, or the sleeve 35 may rotatably receive the ends of both the shafts 33 and 34. In this case the sleeve 35 would be supported by brackets or the like (not shown) securable to the support means 22 for support of the facing inner ends of the shafts 33 and 34.

When the motor 55 is actuated to rotate in a reverse direction, as by actuation of a handle 61 extending through an opening 62 in the side wall 24 of a housing 23, the gears 52 and 53 are rotated in a counterclockwise direction to drive the ring gears 45 and 46 in a clockwise direction, the rotation of the ring gears being transmitted into rotation of the gripping members 57 as previously described to rotate to the gripping members in a clockwise direction, around the stub shafts 56, thereby moving the serrated edges 59 of the gripping members away from the axis 48 and ungrip the workpiece 16. It is to be noted that both ring gears 45 and 46 are driven in an identical direction, therefore the gripping members 57 mounted on the outer face 43 of the flange 45 are mounted oppositely to that illustrated in FIGURE 4 whereby a view looking at the outer face of the ring gear 46 and members 57 would appear identical to the gears of FIGURE 4. As best seen in FIGURES 4 and 5, the teeth 58 of the gripping members 57 are constantly in contact with the internal teeth 49 of the ring gears 45 and 46. The arcuate outer surface of each gripping member is of sufficient peripheral length whereby an end thereof contacts the side edge 63 of an adjacent gripping member 57 to prevent disen gagement of the teeth 5% with the teeth 49 in the pipedisengag'ed position,

To prevent lateral movement of the ring gears 45 and 46 relative to the flange 47, inward movement is prevented by the bearing face 43 of each flange 41 and 42 while outward lateral movement is prevented by inwardly extending .pads or lugs 64 provided on an end cover member 66 which encloses the other end of the machine 15. To further cover and protect the moving parts heretofore described, a cover member 67 is provided to cover the upper portion of the machine, and includes a discrete inner end cap 68. The end covers 66 and 68 are provided with openings 69 to permit insertion of the work piece 16 therethrough and are aligned with the interior of the hollow shaft 32. The opening 69 of the end cover 66 is preferably convexly formed to space its opening 69 from the ring gear 45 and its associated gripping members 57 to prevent inadvertent insertion of fingers by the operator of the machine when inserting the workpiece 16 therethrough. The top cover member 67 is preferably provided with an indented portion 71 for storage of die heads forming a part of the thread-cutting means 18 to be hereinafter described.

In order to prevent rotation of the two sections 33 and 34 of the hollow shaft 32 until after the woi kpiece 16 has been securely gripped by the gripping members, a pair of friction bands 72 are provided circumjacent the shaft parts 33 and 34. As best seen in FIGURE 3, each friction band 72 is enclosed by hinged circular straps 73 having a spring biased mounting 74, at one end, to a bracket 76 secured to the side wall 26 of the housing 23.

It will also be. seen by the foregoing description, that the workpiece 16 is securely supportedwithin the supporting means comprising gripping members 57 on each flanged end of the hollow shaft 32, whereby the gripping members 57 automatically center the workpiece 16 within the shaft 32 and grip the workpiece whereby continued rotation-of the gears 45, 46 rotates the shaft 32 and the workpiece 16 with a minimum of parts. The gripping means on the axially spaced flanges grip on two surfaces axially spaced on the workpiece, thereby decreasing vibration or wobbling of the workpiece in a radial direction and securely fastening the workpiece 16 against axial movement thereof by providing gripping means which is constantly biased into gripping engagement during rotation, thus providing greater accuracy in the various operations to be performed on the workpiece.

It will be noted that the pivots 56 about which the gripping members or jaws 57 rotate are simply stub shafts that are not subjected to any torsional loading, being loaded only in shear. They are thus in position to transmit a much greater gripping force than if required to transmit the torque from the teeth 49 to the: pipe 16. This is achieved by transmitting the force diametrically across the shaft 56, i.e., by locating thedriving teeth 49 in substantially the same normal (to shaft 56) plane as the serrated edge 59.

Friction is independently applied to the hollow shafts 33 and 34 by each of the friction bands 72 to prevent rotation of the shaft until the respective gripping members 57 have gripped the workpiece 16, after which continued rotation of the ring gears 45 and 46 causes the driving force applied thereto to be applied through the gripping members 57 to the stub shafts 56 of each flange 41, 42 to rotate the shafts 33 and 34. The initial rotational movement of the ring gears 45 and 46 is translated into rotational movement of the gripping members 57 to bring serrated edges 59 into engagement with the workpiece 16, after which continued rotation is transmitted to the stub shafts 56 and the adjacent flanges 41 and 42 to rotate the shafts 33 and 34.

By the provision of separately rotatable hollow shafts 33, 34, one of the shafts may continue to rotate after the other one has actuated its gripping members 57 in the event that the outer surface of the workpiece 16 associated therewith is larger than the outer diametrical surface of the shaft 16 associated with the other set of gripping members 57 of the other hollow shaft, such as the shaft 34. The other hollow shaft 34 may be independently retarded from rotation by its friction band 72 to permit the gripping members 57 thereof to come into firm gripping engagement with the shaft portion having a smaller outer diametrical surface. In this manner both sets of gripping members 57 of the shafts 33 and 34 are biased into gripping engagement of the work-piece 16 to firmly support the workpiece in a true and aligned centerless support.

While the instant invention has been shown and described herein in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention which is therefore not to be limited to the details disclosed herein but is to be afforded the full scope of the claims.

What I claim as new and desire to secure by Letters Patent is:

1. A workpiece working machine comprising: support means, a pair of independently rotatable coaxial chuck members having an axial passage way therein adapted to receive an elongate member such as a pipe or rod to be gripped by the machine, a pair of annular driving rings rotatably and coaxially mounted adjacent the respective said chuck members, gripping means interconnecting each annular ring and th respective chuck member and effective to be moved inward toward the axis upon relative rotation in a given direction between said ring and chuck member, said gripping means being spaced axially of each other and adapted to grip a member positioned generally on said axis, each of said rings having external gear teeth thereon, a pair of pinions meshed respectively with the teeth of said driving rings, and motive means for simultaneously rotating said pinions, thereby simultaneously rotating said driving rings and thus apply gripping force to said gripping members.

2. A workpiece Working machine comprising: support means, a pair of chuck plates independently rotatably mounted on said support means, each having a substantially centrally located hole therein, said holes being aligned and spaced along the rotation axis and adapted to receive an elongate member such as a pipe or rod to be gripped by the machine, a pair of annular driving rings mounted respectively adjacent said chuck plates and coaxially therewith, a pair of gripping means interconnected respectively between each annular ring and its respective chuck plate and effective to be moved inward toward said axis upon relative rotation in a given direction between ring and plate, said gripping means being adapted to grip a member positioned in said machine and generally on said axis, each of said rings having external gear teeth thereon, a pair of pinions meshed respectively with the teeth of said driving rings, and motive means for simultaneously rotating said pinions, thereby to simutaneously rotate said driving rings and thus apply gripping force to both of said gripping means.

3. A workpiece working machine comprising support means, a pair of rotatable, coaxial chuck members mounted on said support means for rotation independent of each other, and spaced along the axis of rotation, said chuck members being adapted to receive generally on said axis an elongate member such as a pipe or rod to be,

gripped by the machine, gripping means one on each of said chuck members, efliective to be moved inward toward said axis, drive means linked to said chuck members via the respective gripping means for rotating said chuck members and for moving said gripping means inward to grip said elongate member, each of said gripping means being inwardly movable independently of the other, whereby firm gripping of said elongate member is achieved at two spaced regions along its length irrespective of possible differential in cross section of said longate member at said spaced regions.

4. A workpiece working machine comprising: support means, a pair of chuck plates coaxially rotatably mounted independent of each other on said support means, each having a substantially centrally located hole therein, said holes being aligned and spaced along the rotation axis and adapted to receive an elongate member such as a pipe or rod to be gripped by the machine, drive means for rotating said chuck plates, a pair of gripping means, each interconnected between said drive means and its respec tive chuck plate and effective to be moved inward toward said axis upon relative rotation in a given direction between said drive means and the respective plate, rotation of said chuck plates being effected by said drive means via said gripping means, said gripping means being adapted to grip a member positioned in said machine and generally on said axis, whereby upon motivation from said drive means, said gripping means are moved inward until relative movement between said gripping means and its respective chuck plate is stopped by engagement of the gripping means with the surface of the elongate member and thereafter the chuck plate is rotated by said drive means via its respective gripping means.

5. A workpiece working machine comprising: support means, a pair of chuck members mounted on said support means for rotation coaxial an independent of each other, each having a substantially centrally located hole therein, said holes being aligned and spaced along the rotation axis and adapted to receive an elongate member such as a pipe or rod to be gripped by the machine, a pair of annular driving rings mounted respectively adjacent said chuck members and coaxially therewith, gripping means interconnected between said annular ring and a respective chuck member and effective to be moved inward toward said axis upon relative rotation in a given direction between ring and chuck member, said gripping means being adapted to grip said elongate member positioned in said machine generally on said axis, each of said rings having external gear teeth thereon, rotation of said annular ring being transmitted to its respective chuck member via the respective gripping means, a pair of pinions meshed respectively with the teeth of said driving rings, and a double ended motor located between said rings and having respective output shaft means extending from opposite ends thereof adjacent said rings, said pinions being mounted respectively on said output shaft means, said motor serving to simultaneously rotate said driving rings and thus apply gripping force to said gripping members.

6. A workpiece working machine comprising: support means, a pair of chuck members rotatably mounted coaxially on said support means, each having a substantially centrally located hol therein, said holes being aligned and spaced along the rotation axis of said chuck members and adapted to receive an elongate member such as a pipe or a rod to be gripped by the machine, said chuck members being rotatable independently of each other, drag means for applying a braking force to said chuck members, drive means for rotating said chuck members, a pair of gripping means interconnected between said drive means and the respective chuck members, each effective to be moved inward toward said axis upon relative rotation in a given direction between said drive means said drive means, said gripping means are moved inwardly until relative movement between said gripping means and its respective chuck member is stopped by engagement of the gripping means with the surface of the elongat member, and thereafter said chuck member is rotated by said drive means 'via said gripping means.

7. A workpiece working machine comprising: a base, a pair of chuck members rotatably mounted on said base for coaxial rotation independently of each other, each said chuck member including a hollow shaft portion disposed coaxially of the axis of rotation, said shaft portions being aligned and adapted'to receive an elongate member such as a pipe or a rod to be gripped by the machine, pair of brake means engaging respectively said shaft portions for applying drag to said chuck members, drive means for rotating said chuck members, a pair of gripping means spaced along said axis and interconnected between said drive means and a respective chuck member, and effective to be moved inward toward said axis upon relative rotation in a given direction between said drive means and the respective chuck member, rotation of each said chuck member being effected by said drive means via its respective said gripping means, said gripping means being adapted to grip an elongate member positioned in said machine generally on said axis, whereby upon motivation of said drive means, said gripping means are moved inwardly until relative movement between said gripping means and its respective chuck plate is stopped by engagement of the gripping means with the surface of the elongate member, and thereafter the chuck member is rotated by said drive means via its respectiv gripping means.

References (Iited by the Examiner UNITED STATES PATENTS 1,235,074 7/1917 Stahl 10-87 1,775,592 9/ 1930 Harrison 2791.3 1,801,730 4/1931 Elliott 7773 2,547,195 4/ 1951 Calieudo 77-73 2,692,996 11/ 1954 Wallace 10-87 2,723,861 11/1955 Eisler 279- 106 2,792,735 5/1957 Ice -i. a. 279106 2,885,698 5/1959 Bjalme 10-422 2,916,290 12/1959 Skillin 279-406 2,938,222 5/1960 Bjalme 101-22 2,980,434 4/ 1961 Hofiman 279106 3,005,638 10/1961 McConnell 279-406 ROBERT C. RIORDON, Primary Examiner.

CARL W. TUNLIN, ANDREW R. JUHASZ, Examiners. 

1. A WORKPIECE WORKING MACHINE COMPRISING: A SUPPORT MEANS, A PAIR OF INDEPENDENTLY ROTATABLE COAXIAL CHUCK MEMBERS HAVING AN AXIAL PASSAGE WAY THEREIN ADAPTED TO RECEIVE AN ELONGATE MEMBER SUCH AS A PIPE OR ROD TO BE GRIPPED BY THE MACHINE, A PAIR OF ANNULAR DRIVING RING ROTATABLY AND COAXIALLY MOUNTED ADJACENT THE RESPECTIVE SAID CHUCK MEMBERS, GRIPPING MEANS INTERCONNECTING EACH ANNULAR RING AND THE RESPECTIVE CHUCK MEMBER AND EFFECTIVE TO BE MOVED INWARD TOWARD THE AXIS UPON RELATIVE ROTATION IN A GIVEN DIRECTION BETWEEN SAID RING AND CHUCK MEMBER, SAID GRIPPING MEANS BEING SPACED AXIALLY OF EACH OTHER AND ADAPTED TO GRIP A MEMBER POSITIONED GENERALLY ON SAID AXIS, EACH OF SAID RINGS HAVING EXTERNAL GEAR TEETH THEREON, A PAIR OF PINIONS MESHED RESPECTIVELY WITH THE TEETH OF SAID DRIVING RINGS, AND MOTIVE MEANS FOR SIMULTANEOUSLY ROTATING SAID PINIONS, THEREBY SIMULATANEOUSLY ROTATING SAID DRIVING RINGS AND THUS APPLY GRIPPING FORCE TO SAID GRIPPING MEMBERS. 